Yang deficiency usually refers to the failure of the yang energy of the kidneys, and is a symptom of the failure of the yang energy of the kidneys. Most of the symptoms are caused by Yang deficiency in the body, or by kidney deficiency in old age, or by long-term illnesses that injure the kidneys, or by overexertion in the room. The clinical manifestations are soreness in the waist and knees, coldness in the extremities, especially in the lower extremities, such as ankles and calves, edema, and fear of cold, including dizziness, dazzling, depression, and pallor, or in severe cases, impotence and premature ejaculation. In women, it may lead to infertility due to coldness in the uterus, or prolonged diarrhea in the stool. Swelling is an obvious symptom of kidney yang deficiency, which is a series of symptoms from the waist down to the ankle part or the calf, where there are indentations when the hand is pressed down, or even abdominal distension, palpitations, and cough.